Asymmetric septal hypertrophy may also be associated with Q waves that simulate a transmural infarction. The left-to–right electrical forces that occur in association with septal depolarization are unopposed and normally cause the small Q waves seen in the left sided leads, the “septal Q waves.” When there is asymmetric hypertrophy of the interventricular septum, these unopposed forces will increase in magnitude and duration producing Q waves that resemble those of a myocardial infarction.